eVidyarthi

Ultrasound and Human Ear, Class 9 Science

1. There will be total 10 MCQ in this test.
2. Please keep a pen and paper ready for rough work but keep your books away.
3. The test will consist of only objective type multiple choice questions requiring students to mouse-click their correct choice of the options against the related question number.
4. No negative marking for incorrect choice.
5. Please click on “Finish the Test” when you want to exit.
6. All the best – Happy Studying

1. Which waves are employed in SONAR?
 
 
 
 

Question 1 of 10

2. A ship sends sonar and receives an echo after 2 seconds. If the speed of sound waves in water is 1500 m/s, then the depth of the sea is
 
 
 
 

Question 2 of 10

3. The vibrations or the pressure variations inside the inner ear are converted into electrical signals by the:
 
 
 
 

Question 3 of 10

4. Which part of the ear amplifies the vibrations of eardrum?
 
 
 
 

Question 4 of 10

5. Sound of the frequency below 20 Hz is known as
 
 
 
 

Question 5 of 10

6. The technique used by bats to find their way or to locate food is
 
 
 
 

Question 6 of 10

7. Ultrasound is not used to:
 
 
 
 

Question 7 of 10

8. Young children below 5 year can hear up to a frequency of
 
 
 
 

Question 8 of 10

9. The velocity of ultrasonic sound in water is 1400 m. The depth of the ocean as detected by SONAR, if the time taken to receive the reflected wave is 15s, is
 
 
 
 

Question 9 of 10

10. A ship on the surface of water sends a signal and receives it back after 4 seconds from a submarine inside the water. Calculate the distance of the submarine from the ship (The speed of sound in water is 1450 m/s).
 
 
 
 

Question 10 of 10